1. Field
The subject matter described herein relates generally to a motor operator for circuit breakers.
2. Related Art
It is known in the art to provide molded case circuit breakers for electrical systems. The circuit breaker is operative to disengage the electrical system under certain operating conditions. The use of accessories such as, for exemplary purposes only, motor operators to allow the motor-assisted operation of electrical circuit breakers is well known. The motor operator allows the circuit breaker to be operated remotely and to be opened, closed or reset after tripping of the circuit breaker.
The motor operator may be a field mountable device (e.g. an add on device) and is typically secured to the top of a circuit breaker housing. A lever within the motor operator mechanically interacts with a circuit breaker operating handle, which extends from the circuit breaker housing. The lever is operatively connected to a motor within the motor operator. The motor drives the lever, which, in turn, moves the operating handle to operate the circuit breaker. The operating handle is moved between “on”, “off”, and “reset” positions, depending on the rotational direction of the motor.
A plurality of buttons external to the motor operator controls electrical current to the motor. The rotational direction of the motor is changed depending on which of these buttons is selected by operating personnel. Thus, the operating personnel can select one button to place the operating handle in the “on” position, and another button to place the operating handle in the “off” or “reset” positions.
When the handle is moved to the “on” position, electrical contacts within the circuit breaker are brought into contact with each other, allowing electrical current to flow through the circuit breaker. When the handle is moved to the “off” position, the electrical contacts are separated, stopping the flow of electrical current through the circuit breaker. When the handle is moved to the “reset” position, an operating mechanism within the circuit breaker is reset, as is necessary after the operating mechanism has tripped in response to an overcurrent condition in the electrical circuit being protected by the circuit breaker.
In one example, a motor operator may be mounted to circuit breaker in a vertical orientation such as when the circuit breaker is mounted on a wall. Motor operators may be heavy and difficult for a single technician to mount on the breaker. For example, it is difficult at best for a single technician to hold the motor operator on the vertically mounted breaker while the technician is trying to install the fasteners that secure the motor operator to the breaker.
It would be advantageous to have a circuit breaker add on device, such as a motor operator, that is easily mounted to a circuit breaker.